Back to results
US 4,015,571 AGranted
Fuel-air mixture controller for internal combustion engines
AssigneeRobert Bosch GmbH
InventorGerhard Stumpp
Life of this patent
Estimating the term…
Abstract
An air flow rate sensor, located in the induction tube of an internal combustion engine, displaces a fuel metering slide, thereby changing the fuel flow and the fuel pressure gradient. This pressure gradient is applied to a differential pressure valve which actuates a fuel flow control throttle until the pressure gradient has been restored to a nominal value, corresponding to a desired fuel-air ratio. In a variant embodiment, an arbitrary change in the metered out fuel results in a fuel pressure gradient which is used to reset an air-flow control member until the nominal value of the pressure gradient has been restored, corresponding to a desired fuel-air ratio.
Claims8
A fuel-air ratio regulator for an internal combustion engine, comprising:
- a. an air induction tube;
- b. a fuel injection pump;
- c. a primary fuel pump;
- d. a fuel line connecting the primary fuel pump to the fuel injection pump;
- e. an air quantity measuring member, having a portion thereof disposed in said air induction tube for displacement therein under the influence of an air stream drawn into said air induction tube;
- f. means mounting said air quantity measuring member for effecting the displacement within said air induction tube;
- g. first fuel control means, connected in the fuel line between said primary fuel pump and said fuel injection pump and actuated by said air quantity measuring member;
- and
- h. second fuel control means, connected in the fuel line between said first fuel control means and said fuel injection pump and actuatable by said first fuel control means so that said second fuel control means meters out a fuel quantity which maintains a predetermined desired fuel-air ratio wherein said first fuel control means includes:
- i. a fuel valve with a movable valve member actuated mediately by said air quantity measuring member, whereby motions of said movable valve member tend to produce changes in the pressure gradient across said fuel valve which are counteracted by said fuel control means, and the flow cross section of said fuel valve corresponds to the air quantity aspirated by the engine;
- ii. a differential pressure valve connected both upstream and downstream of said fuel valve;
- and
- iii. a servo motor connected in the fuel line between said pressure differential valve and said second fuel control means, said servo motor being actuated by said differential pressure valve to influence the operation of said second fuel control means.
10 more elements
In an internal combustion engine employing stratified charge fuel delivery, the combination comprising:
- a. an air induction tube;
- b. at least one fuel injection pump;
- c. a primary fuel pump;
- d. a fuel line connecting the primary fuel pump to the fuel injection pump;
- e. an air quantity measuring member, having a portion thereof disposed in said air induction tube for displacement therein under the influence of an air stream drawn into said air induction tube;
- f. means mounting said air quantity measuring member for effecting the displacement within said air induction tube;
- g. first fuel control means, connected in the fuel line between said primary fuel pump and said fuel injection pump and actuated by said air quantity measuring member;
- and
- h. second fuel control means, connected in the fuel line between said first fuel control means and said fuel injection pump and actuated by said first fuel control means so that said second fuel control means meters out a fuel quantity which maintains a predetermined desired fuel-air ratio wherein said first fuel control means includes:
- i. a fuel valve with a movable valve member actuated mediately by said air quantity measuring member, whereby motions of said movable valve member tend to produce changes in the pressure gradient across said fuel valve which are counteracted by said second fuel control means, and the flow cross section of said fuel valve corresponds to the air quantity aspirated by the engine;
- ii. a differential pressure valve connected both upstream and downstream of said fuel valve;
- and
- iii. a servo motor connected in the fuel line between said pressure differential valve and said second fuel control means, said servo motor being actuated by said differential pressure valve to influence the operation of said second fuel control means.
10 more elements
In an internal combustion engine employing self-ignition, the combination comprising:
- a. an air induction tube;
- b. a fuel injection pump;
- c. a primary fuel pump;
- d. a fuel line connecting the primary fuel pump to the fuel injection pump;
- e. an air quantity measuring member, having a portion thereof disposed in said air induction tube for displacement therein under the influence of an air stream drawn into said air induction tube;
- f. means mounting said air quantity measuring member for effecting the displacement within said air induction tube;
- g. first fuel control means, connected in the fuel line between said primary fuel pump and said fuel injection pump and actuated by said air quantity measuring member;
- and
- h. second fuel control means, connected in the fuel line between said first fuel control means and said fuel injection pump and actuatable by said first fuel control means so that said second fuel control means meters out a fuel quantity which maintains a predetermined desired fuel-air ratio wherein said first fuel control means includes:
- i. a fuel valve with a movable valve member actuated mediately by said air quantity measuring member, whereby motions of said movable valve member tend to produce changes in the pressure gradient across said fuel valve which are counteracted by said second fuel control means, and the flow cross section of said fuel valve corresponds to the air quantity aspirated by the engine;
- ii. a differential pressure valve connected both upstream and downstream of said fuel valve;
- and
- iii. a servo motor connected in the fuel line between said pressure differential valve and said second fuel control means, said servo motor being actuated by said differential pressure valve to influence the operation of said second fuel control means.
10 more elements
Dependencies are inferred from the claim text.